Automotive manufacturers constantly look for innovative ways to reduce vehicle cost, without sacrificing quality. One widely known strategy is to lower cost by reducing production time. Accordingly, manufacturers apply clips rather than fasteners such as screws, bolts, nuts, or the like for securing various components throughout the interior and exterior of the vehicle. It is well known that nuts have been used to secure heat shields to various metallic and non-metallic surfaces. However, for every nut used in such a manner, time is required to install the nuts into position. In fact, given the tight confines of an engine compartment, providing the required twisting action to the nut can be extremely difficult. As a result, there is a need for a thread cage retainer that can be quickly inserted, yet securely retained on, a threaded stud. Such a retainer should simulate a nut, and require a twisting action for removal, but should also advantageously eliminate the time required to secure a conventional nut into position.
There have been several attempts to create such devices, however, they lack structure which guarantees appropriate alignment and heat properties provided by steel. One such device is disclosed in U.S. Pat. No. 5,110,246. This patent discloses a fastener that has a cap and a set of teeth at the base. Although the fastener disclosed is beneficial, it lacks versatility because it cannot be used on varying heights of threaded studs. Another disadvantage of this fastener is that the closed cap structure prevents any expansion other than that of the engaging teeth.
Another device is disclosed in U.S. Pat. No. 4,990,044. Although effective for its intended purposes, this retainer lacks the ability to be used in heat applications based on the materials disclosed in the specification. Furthermore, this device includes an internally threaded nut portion peripherally split in an axial direction to permit radial expansion. Although this configuration is beneficial, there exists a need to provide a decreased installation force where only a portion of the engaging surface communicates with the threads of a threaded stud.
As a result, there is a need for a retainer that can be quickly inserted, yet securely retained on, a threaded stud. Such a retainer should simulate a nut and require a twisting action for removal, but should also advantageously eliminate the time required to secure a conventional nut into position.